Cellular networks and Wireless Local Area Networks (“WLANs”) enable communications between mobile wireless devices such as mobile phones and portable computers and fixed location wireless devices such as access points and base stations. It is naturally desirable to test the performance of such devices under different conditions. However, testing wireless devices in an open environment is notoriously difficult because wireless communications can be affected by ambient sources of interference. It is now relatively common to use simulators to perform wireless device testing in a closed environment. One type of simulator includes an EMI-shielded container for each wireless device. Communications are converted from wireless RF to conducted electrical signals, and the containers are placed in communication via wired connections. Emulation modules connected between the containers subject the communications to simulated physical environmental effects including but not limited to multipath reflections, delay spread, angle of arrival, power angular spread, angle of departure, antenna response and geometry, Doppler from moving vehicle, Doppler from changing environments, path loss, shadow fading effects, reflections in clusters, and Doppler due to fluorescent light effects. Simulators provide some advantages over open air testing. However, the architectures of known simulators do not scale well, which is a problem when it is desirable to test interactions between ones of a relatively large number of wireless devices.